Research Of The Measurement System For Drillstring Whirling Simulation Experimental Platform

The drill string is the indispensable and important downhole tool in oil drilling engineering, and is usually under pull, pressure, bending, torsion and hydraulic load in the work of the well. Under the action of ground power, it not only revolves on its own axis but also has whirling motion. Especially considering the dynamic lubrication of drilling fluid, the drill string under pressure in the case of a vortex, is more easily to lead to wear and fatigue fracture. Therefore, it has a great reference value to carries on the drill string whirling simulation experiments for solving the actual drilling problems encountered in the vortex of the drill string.Firstly, the early measurement system is established on the basis of the drill string whirling simulation experimental bench. It measured the related parameters through the combination of hardware and software, such as the liquid pressure in the buckling drill string surrounding, the stress on the top of the drill string, etc. Again through the study of the comparison and analysis of the collected parameters, an important conclusion was proposed that with the increase of rotational speed, the drill rotated from a relatively stable state to an unstable state, and then back to the relative stabile state. It provided a powerful experimental basis for the vortex motion theory research results of drill string.Again, considering the practical application of the measuring system, I researched the overall design of the improved measuring system on the basis of preliminary measurement system, including the hardware design and software design. Hardware design including the selection of liquid pressure sensors, drawing displacement sensor, axial pressure sensor, image sensor and data acquisition card and so on; Software design is to develop a measurement system based on Lab-view platform, and to write binocular stereo vision procedure with VC+ + and the Open CV vision binocular, together to meet the measuring need of the whirling simulation experimental bench and the future application requirements.